The EARTH Study is unique in that it included questions regarding AN/AI traditional diet and physical activities as well as foods and activities more commonly included in assessments of the general population. The study allowed assessment of traditional physical activity and dietary patterns among AN/AI peoples living in urban, rural and remote settings and associations with cultural factors. These data provide baseline information for further examination of changing patterns of traditional food use and physical activity.
Acculturation to a more Western life-style has been postulated as an important factor in the development of chronic diseases (23
). One of the most common ways in which acculturation is evident is in the changing mixture of traditional and store-bought foods. Data are limited on food consumption of Alaska Native people. However, some general trends include substantial regional and seasonal variation in food-intake patterns, as well as an overall decline in consumption of traditional foods (24
). An increasing reliance upon store-bought food sources has likely further decreased participation in traditional activities and traditional food consumption. Lending support to this is the finding by the EARTH Study that participants who consumed traditional foods and did traditional activities were also more likely to strongly identify with their cultural traditions and carry out more cultural practices.
The Alaska Traditional Diet Survey (ATDS, 2004) found a substantial reliance of Alaska Native peoples on many traditional foods such as fish, terrestrial mammals, marine mammals and wild plants. They found a similar percentage of people reporting fish use across regions as did the EARTH Study, but a much higher percentage of traditional foods reported overall, especially berries and wild greens across all areas, deer in the south-east region and marine mammals in the south-west (4
). Differences between the 2 studies may have to do with the more limited sample size as well as the preponderance of rural communities surveyed by the ATDS, whereas the EARTH Study included over 1,000 Alaska Native participants in and near the largest city in Alaska, who reported fewer traditional foods than those in more remote areas. There were sex differences in reported use of specific traditional foods, but not in overall reported traditional food use by EARTH Study participants. This finding was similar to a study among the Belcher Island Inuit in Canada, which found no significant sex differences in household estimates of traditional foods, either combined or by food group (25
). Older EARTH Study participants were also more likely to report consuming traditional foods, which has been noted in other studies of circumpolar Indigenous peoples (7
Gender differences in overall physical activity have been noted previously in this cohort (17
), and other studies have also classified AN/AI and First Nations women as less physically active than their male counterparts (8
). A study of energy expenditure in the Yakut of Siberia found that more men than women participated in traditional tasks (5
), a pattern that was also found among EARTH Study participants. Other factors associated with traditional activity participation were living in a rural area, speaking a Native language, having a higher annual income, and not being employed. While the association with both higher income and lack of employment might seem contradictory, there are several possible explanations. First, the cut-off point for income in the EARTH Study was $15,000 per annum, so income levels categorized as high might still be considered low in other population-based studies. In addition, we examined total household income. Therefore, one member of the family could participate in traditional activities and not be in the work force while another was engaged in wage labour, in which case participants could be in the higher income group but still not be employed themselves. Our findings of the trade-offs between traditional activities and employment were in agreement with an econometric study of Alaska’s North Slope Inupiat people which found an inverse relationship between active subsistence harvesting and wage labour time, although the authors noted that cash from employment was often used for subsistence inputs (i.e., gasoline, boats, ammunition), and redistribution of subsistence harvests played an important role in cultural and community cohesion (28
This study did not investigate possible social influences, such as the importance of sharing food among family and community members, or physical environmental influences on traditional physical activity and food use (26
). Although qualitative research has shown that Native American people believe that the physical environment affects their physical activity participation (27
), little quantitative data exists on environmental supports and barriers in the AN/AI populations surveyed by the EARTH Study. Even in AN communities that lack road access, mechanized transport for traditional activities (four-wheeled all-terrain vehicles, motorized boats) is increasingly common, and no research to date has examined the impact of mechanization in decreasing the physical intensity of traditional activities. A further issue is that climate change in the Arctic is beginning to effect available species and seasonality of harvesting activities, increasing both the risk and the cost of some traditional activities (29
This study has several limitations. The first is the cross-sectional nature of the data, which came from the baseline visit of a prospective cohort study. These data allow for descriptive reporting but not for evaluating associations with health outcomes. We hope that a prospective follow-up of this cohort will help to resolve these issues in the future.
Participants were also not randomly selected, thus conclusions may not be generalizable. However, the distribution of the AN/AI populations surveyed closely resembled the distributions of age and marital status reported by the 2000 U.S. Census (22
), making it likely that the data are generalizable to these regions. Women were over-represented in the study, which may have skewed the total prevalence of foods and activities reported. Additionally, data were collected by self-report, and the current report does not provide quantification of traditional foods eaten, as validation of the diet portion of the EARTH questionnaires is ongoing. However, lending some credibility to the validity of the self-reported data is the consistency in responses; the majority of those who reported consuming traditional foods also reported doing traditional activities.
There have been few studies that have examined how cultural identification and behaviours might positively relate to health factors. A study of African-American men and women found that positive identification with African-American culture was associated with more leisure-time physical activity, lower-fat eating and not smoking (31
). A study among the Omaha Tribe in Nebraska reported that high cultural identity was positively correlated with control of diabetes in terms of blood sugar levels (32
), while another study of American Indian women found that cultural pride was a source of physical activity (33
). A strong positive finding of the EARTH Study was the interrelationship between traditional food use, traditional physical activities and tribal and cultural activities and behaviours.
Our findings show that traditional activities and foods are an important component of the physical activity and food intake of Alaska Native and American Indian peoples in Alaska, and are associated with a stronger attachment to tribal and cultural identity. These data can be used to design health-promotion efforts with this population to improve overall health and wellness. Traditional harvesting activities and foods may play an important role in modifying health risks and protecting American Indian and Alaska Native peoples from increasingly common chronic diseases such as diabetes, heart disease, stroke and cancer.